Bryant 581A/B manual 150

ELECTRICAL DATA (cont)

151	UNIT SIZE	NOMINAL	IFM	CONV	VOLTAGE RANGE		COMPRESSOR (each)			OFM (each)		IFM	COMBUSTION	POWER SUPPLY		MINIMUM UNIT
													FAN MOTOR			DISCONNECT SIZE*
	580F	V-PH-Hz	TYPE	OUTLET								FLA
580F036-					Min	Max	Qty	RLA	LRA	Qty	FLA		FLA	MCA	MOCP†	FLA	LRA
				NO										29.6	35	31	192
			STD	NO								10.6		65.2	80	68	383
		208/230-3-60		YES	187	254	2	23	146	2	1.4		0.6	71.2	80	74	387
			HIGH	NO								15.0		69.6	80	73	406
				YES										75.6	80	79	410
			STD									4.8
	150	460-3-60		YES	414	508	2	10.4	73	2	0.7		0.3	35.6	40	34	194
	(121/2 Ton)		HIGH	NO								7.4		32.2	35	34	203
				YES										34.9	40	37	205
			STD	NO								2.0		23.6	30	25	154
		575-3-60		YES	518	632	2	8.3	58.4	2	0.6		0.3	29.6	35	27	156
			HIGH	NO								2.8		25.7	30	27	163
				YES										31.7	35	29	165
			STD	NO								10.6		56.2	70	59	359
		208/230-3-60		YES	187	254	2	19	156	2	1.4		0.6	61.0	70	65	364
			HIGH	NO								15.0		60.6	70	64	378
				YES										65.4	80	70	383
			STD	NO								4.8		26.5	30	28	174
	151	460-3-60		YES	414	508	2	9	75	2	0.7		0.3	28.7	35	30	176
	(121/2 Ton)		HIGH	NO								7.4		29.1	35	31	213
				YES										31.3	35	33	215
			STD	NO								3.3		21.6	25	23	127
		575-3-60		YES	518	632	2	7.4	54	2	0.6		0.3	23.3	30	25	129
			HIGH	NO								5.6		23.7	25	25	159
				YES								5.6		25.4	30	27	160

LEGEND

Determine percent of voltage imbalance.

FLA — Full Load Amps

% Voltage Imbalance = 100 x

7

HACR	— Heating, Air Conditioning and Refrigeration
IFM	— Indoor (Evaporator) Fan Motor
LRA	— Locked Rotor Amps
MCA	— Minimum Circuit Amps
MOCP — Maximum Overcurrent Protection
NEC	— National Electrical Code
OFM	— Outdoor (Condenser) Fan Motor
RLA	— Rated Load Amps

*Used to determine minimum disconnect per NEC. †Fuse or HACR circuit breaker.

NOTES:

1.In compliance with NEC requirements for multimotor and combination load equipment (refer to NEC Articles 430 and 440), the overcurrent protective device for the unit shall be fuse or HACR breaker. Canadian units may be fuse or circuit breaker.

2.Unbalanced 3-Phase Supply Voltage

Never operate a motor where a phase imbalance in supply voltage is greater than 2%. Use the following formula to determine the percent of voltage imbalance.

% Voltage Imbalance

max voltage deviation from average voltage

= 100 x

average voltage

Example: Supply voltage is 460-3-60.

AB = 452 v

BC = 464 v

AC = 455 v

452 + 464 + 455

Average Voltage =

3

1371

=

3

= 457

Determine maximum deviation from average voltage. (AB) 457 – 452 = 5 v

(BC) 464 – 457 = 7 v (AC) 457 – 455 = 2 v

Maximum deviation is 7 v.

457

= 1.53%

This amount of phase imbalance is satisfactory as it is below the maximum allowable 2%.

IMPORTANT: If the supply voltage phase imbalance is more than 2%, contact your local electric utility company immediately.

3.For units with power exhaust: If a single power source is to be used, size wire to include power exhaust MCA and MOCP. Check MCA and MOCP when power exhaust is powered through the unit (must be in accordance with NEC and/or local codes). Determine the new MCA including the power exhaust using the following formula:

MCA New = MCA unit only + MCA of Power Exhaust

For example, using a 580F060 unit with MCA = 28.9 and MOCP = 35, with CRPWREXH030A01 power exhaust.

MCA New = 28.9 amps + 1.6 amps = 30.5 amps

If the new MCA does not exceed the published MOCP, then MOCP would not change. The MOCP in this example is 35 amps, the MCA New is below 35, therefore the MOCP is acceptable. If “MCA New” is larger than the published MOCP, raise the MOCP to the next larger size. For separate power, the MOCP for the power exhaust will be 15 amps per NEC.

POWER EXHAUST ELECTRICAL DATA

					MOCP
POWER EXHAUST	APPLICATION	MCA	MCA	MCA	(separate
PART NO.	USAGE	(230 V)	(460 V)	(575 V)	power source
					only)
CRPWREXH030A01	036-073*	1.6	N/A	0.64	15
CRPWREXH021A01	036-073	N/A	0.68	N/A	15
CRPWREXH022A01	090-151*	3.4	N/A	1.32	15
CRPWREXH023A01	090-151	N/A	1.4	N/A	15
CRPWREXH028A01	ALL*	1.7	N/A	0.68	15
CRPWREXH029A01	ALL	N/A	0.7	N/A	15

*Single or three phase.

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